Developmental toxicity and mechanism of polychlorinated biphenyls 126 and nano-polystyrene combined exposure to zebrafish larvae.

3,3',4,4',5-Pentachlorobiphenyl (PCB126) is the most toxic congener of dioxin-like polychlorinated biphenyls (DL PCBs), while nanoplastics (NPs) have recently emerged as significant marine pollutants, both posing threats to aquatic organisms and human health. They coexist in the environment, but their comprehensive toxicological effects remain unclear. In this study, zebrafish embryos were simultaneously exposed to PCB126 and 80-nanometer nanoplastyrene (NPS). Researchers utilized fluorescence microscopy, qPCR, histopathological examination, and transcriptomic sequencing to investigate the developmental toxicity of different concentrations of PCB126 and NPS individually or in combination on zebrafish embryos and larvae. Results indicate that the chorion significantly impedes the accumulation of NPS (p < 0.05). It is noteworthy that this barrier effect diminishes upon simultaneous exposure to PCB126. In this experiment, the semi-lethal concentration of PCB126 for larvae was determined to be 6.33 µg/L. Exposure to PCB126 induces various deformities, primarily mediated through the aryl hydrocarbon receptor (AHR). Similarly, exposure to NPS also activates AHR, leading to developmental impairments. Furthermore, transcriptomic sequencing revealed similar effects of PCB126 and NPS on the gene expression trends in zebrafish larvae, but combined exposure to both exacerbates the risk of cancer and induces more severe cardiac toxicity. At this level, co-exposure to PCB126 and NPS adversely affects the development of zebrafish larvae. This study contributes to a deeper understanding of the in vivo accumulation of DL polychlorinated biphenyls and microplastics in actual aquatic environments and their impact on fish development.

Identification and Parametrization of Key Factors Affecting Levoglucosan Emission During Solid Fuel Burning.

Levoglucosan (LG) is a pyrolysis product of cellulose and hemicellulose at low combustion temperatures. However, LG release cannot be determined only by considering the contents of cellulose and hemicellulose exclusively due to the complexity of combustion processes and the physical-chemical properties of the fuel. This study detected the emission factors (EFs) of LG from 22 different solid fuel samples (including coal and biomass) by considering 18 different fuel properties and five combustion parameters. The average LGEFs during solid fuel burning varied in a range of 0.03-136 mg kg-1, with a magnitude difference of 1-4 orders. While the variations in cellulose (59.5-368 mg g-1) and hemicellulose (73.5-165 mg g-1) contents of fuel samples were only one- to 6-fold. A short combustion duration (<150 min) and a medium combustion temperature (200-400 °C) influenced by volatile and ash contents are crucial for the generation and accumulation of LG. A random forest coupled with the Akaike information criterion stepwise regression model successfully explained 96% of the total LG emission variation using three variables (ash content, cellulose content, and modified combustion efficiency). The ash content promoted coke formation and LG chain cracking by increasing the pyrolysis temperature and is considered the most important factor. The alkali metal in ash can reduce the energy barrier of intramolecular ring contraction reactions and inhibit the dehydration reactions, which led to additional heat being utilized by the competitive pathways of LG formation. This study provided a method to address the parametrization and release mechanisms of combustion source emissions.

Effects of Microplastics on Microbial Community in Zhanjiang Mangrove Sediments.

Microplastics are easily consumed by marine animals, thereby entering the food chain and endangering animal health. However, there are few studies focusing on the effects of microplastics in mangrove sediments on microbial communities. In order to study the influence of microplastics on microorganisms, microplastics and microorganisms were extracted from Zhanjiang (Guangdong Province, China) mangrove sediments and analyzed. The results showed that there were differences in Shannon and Simpson indices of the microbial community in microplastics (p < 0.05), and there were also differences between JG30_KF_CM45 and Natranaerovirga at the genus level, indicating that microplastics may affect the diversity and composition of microorganisms in sediments. In addition, FAPROTAX function prediction analysis showed that microplastics may affect the nitrification of microbial communities. The results from this study indicate that microplastics affected the diversity and richness of microorganisms in mangrove sediments, which provides an experimental basis for the relationship between microplastics and microorganisms.

Evaluation of Novel Anticaries Adhesive in a Secondary Caries Animal Model.

We investigated the anticaries properties of an adhesive containing dimethylaminododecyl methacrylate (DMADDM) in vivo via a secondary caries animal model. Cavities were prepared in the maxillary first molars of Wistar rats. DMADDM-containing adhesives were applied on one side and commercial adhesives on the opposite side as a control. After a 3-week feeding period to induce secondary caries, the molars were harvested for the evaluation of the secondary caries. Lesion depth (LD) and mineral loss (ML) were measured via a micro-CT method, and a modified Keyes scoring method yielded scores for the caries lesions. Statistical analysis was divided into 2 parts: a correlation analysis between 2 evaluations with one-way ANOVA and a least-significant differences (LSD) test, and an evaluation of anticaries adhesives with a paired samples t test. The results showed that: (1) secondary caries was successfully produced in rats; (2) there was a correlation between the modified Keyes scoring method and micro-CT in the evaluation of the secondary caries; (3) the adhesive containing DMADDM significantly reduced both LD and ML (according to micro-CT), and also lowered the scores (based on the modified Keyes scoring method). This suggests that the novel DMADDM adhesive could perform an anticaries function in vivo via the secondary caries animal model which was also developed and testified in research. Secondary caries is one of the major reasons leading to the failure of caries restoration treatment. As a solution, anticaries adhesives perform well in biofilm inhibition in vitro. However, the lack of secondary caries animal models limits the evaluation of anticaries adhesives in vivo.

Genomics insights into different cellobiose hydrolysis activities in two Trichoderma hamatum strains.

BACKGROUND: Efficient biomass bioconversion is a promising solution to alternative energy resources and environmental issues associated with lignocellulosic wastes. The Trichoderma species of cellulolytic fungi have strong cellulose-degrading capability, and their cellulase systems have been extensively studied. Currently, a major limitation of Trichoderma strains is their low production of ß-glucosidases. RESULTS: We isolated two Trichoderma hamatum strains YYH13 and YYH16 with drastically different cellulose degrading efficiencies. YYH13 has higher cellobiose-hydrolyzing efficiency. To understand mechanisms underlying such differences, we sequenced the genomes of YYH13 and YYH16, which are essentially identical (38.93 and 38.92 Mb, respectively) and are similar to that of the T. hamatum strain GD12. Using GeneMark-ES, we annotated 11,316 and 11,755 protein-coding genes in YYH13 and YYH16, respectively. Comparative analysis identified 13 functionally important genes in YYH13 under positive selection. Through examining orthologous relationships, we identified 172,655, and 320 genome-specific genes in YYH13, YYH16, and GD12, respectively. We found 15 protease families that show differences between YYH13 and YYH16. Enzymatic tests showed that exoglucanase, endoglucanase, and ß-glucosidase activities were higher in YYH13 than YYH16. Additionally, YYH13 contains 10 families of carbohydrate-active enzymes, including GH1, GH3, GH18, GH35, and GH55 families of chitinases, glucosidases, galactosidases, and glucanases, which are subject to stronger positive selection pressure. Furthermore, we found that the ß-glucosidase gene (YYH1311079) and pGEX-KG/YYH1311079 bacterial expression vector may provide valuable insight for designing ß-glucosidase with higher cellobiose-hydrolyzing efficiencies. CONCLUSIONS: This study suggests that the YYH13 strain of T. hamatum has the potential to serve as a model organism for producing cellulase because of its strong ability to efficiently degrade cellulosic biomass. The genome sequences of YYH13 and YYH16 represents a valuable resource for studying efficient production of biofuels.

Candida species in periodontitis: A new villain or a new target?

OBJECTIVES: Recent research indicated that fungi might have a role in periodontitis alongside traditional periodontal pathogens. This state-of-the-art narrative review explores current concepts on the involvement of Candida species in periodontitis, and suggests the potential for ecological management of this disease. DATA, SOURCES AND STUDY SELECTION: A literature search was conducted for a narrative review on Web of Science, PubMed, Medline and Scopus about periodontitis associated with Candida species. Published articles, including case reports, case series, observational and interventional clinical trials, and critical appraisals of the literature were retrieved and reviewed. CONCLUSIONS: Several factors predispose individuals to periodontitis associated with Candida species. These include systemic diseases that lead to immunosuppression and oral environment changes such as cigarette smoking. While a consistent significant increase in the detection rate of Candida species in patients with periodontitis has not been universally observed, there is evidence linking Candida species to the severity of periodontitis and their potential to worsen the condition. Candida species may participate in the development of periodontitis in various ways, including cross-kingdom interactions with periodontal pathogens, changes in the local or systemic environment favoring the virulence of Candida species, and interactions between Candida-bacteria and host immunity. CLINICAL SIGNIFICANCE: Mechanical plaque control is the most common treatment for periodontitis, but its effectiveness may be limited, particularly when dealing with systemic risk factors. Understanding the specific role of Candida in periodontitis illuminates innovative approaches for managing the ecological balance in periodontal health.

[Study on the relationship between hepatitis B virus genotypes and the effect of polyethylene glycol-interferon-alpha therapy on HBeAg-positive chronic hepatitis B].

OBJECTIVE: To investigate the efficacy of polyethylene glycol (PEG)-interferon α (PEG-IFNα) in treating HBeAg-positive chronic hepatitis B (CHB) and explore the relationship between hepatitis B virus (HBV) genotypes and the effect of interferon α (IFNα) therapy. METHODS: A total of 199 CHB patients with known genotypes were given subcutaneous injection of PEG-IFNα-2a or PEG-IFNα-2b once a week for 48 weeks, with another 24 weeks follow up. The seroconversion of HBeAg influenced by HBV genotypes were analyzed after discontinuation of treatment. RESULTS: In local area, genotype C was the major genotype [64.32% (128/199) ]. Except serum ALT and AST level, the differences in gender, age, liver inflammation, degree of liver fibrosis, HBeAg level and HBV DNA level between genotype B and C were not statistically significant (all P > 0.05). The seroconversion rate of HBeAg in patients with genotype B at early stage of therapy (3 months) was significantly higher than that of patients with genotype C [26.76% (19/71) vs 10.16% (13/128), χ(2) = 9.330, P = 0.002]. While at the end of follow-up, seroconversion rate of HBeAg in patients with genotype B (followed up for 6 months) was higher than that of patients with genotype C [39.44% (28/71) vs 30.47% (39/128)], but the difference was not statistically significant (χ(2) = 1.645, P = 0.200). By univariate analysis based on log-rank test, the time of HBeAg seroconversion in patients with genotype B was much earlier than that of genotype C [(13.99 ± 0.67) months vs (15.47 ± 0.41) months], but the difference was not statistically significant (P = 0.150). CONCLUSIONS: The seroconversion rate of HBeAg in patients with genotype B treated with PEG-IFNα was significantly higher than that of genotype C in early stage of therapy (3 months), while similar at the end of therapy.

[Liver histopathological features influencing HBeAg seroconversion in patients with HBeAg-positive chronic hepatitis B responding to Peg-IFN treatment].

OBJECTIVE: To investigate the therapeutic efficiency of antiviral treatment with pegylated-interferon (Peg-IFN) for hepatitis B e antigen (HBeAg)-positive chronic hepatitis B (CHB) and to explore whether liver histopathological features or other factors influence the HBeAg seroconversion treatment response. METHODS: Eighty HBeAg-positive CHB patients with diagnosis confirmed by liver puncture were treated with Peg-IFN(2a or 2b)body weight dose, once weekly). At treatment week 48, the rate of HBeAg seroconversion was determined and used to analyze the influence of liver histopathological features (liver biopsy assessment of: inflammation, graded G0 to G4; fibrosis stage, graded S0 to S4), sex, age, differential levels (pre-treatment baseline vs. week 48 post-treatment) of serum alanine transferase (ALT), and HBV DNA, by binary logistic analysis. RESULTS: At week 48, the overall rate of HBeAg seroconversion was 30.0%. The rate of HBeAg seroconversion gradually advanced with increased liver inflammation (X2 = 8.435, P = 0.015): 9.09% of the 22 patients with G1; 31.58% of the 38 patients with G2; 47.30% of the 19 patients with G3; the one patient with G4. In contrast, the rate of HBeAg seroconversion showed a much weaker association with liver fibrosis (X2 = 5.917, P = 0.116). Only baseline HBeAg level, and no other baseline index, was significantly different between the patients who achieved HBeAg seroconversion and those who did not. Liver inflammation and baseline HBeAg level were identified as influencing factors of HbeAg seroconversion in response to Peg-IFN treatment. CONCLUSION: Peg-IFN therapy induces a higher rate of HBeAg seroconversion in HBeAg-positive CHB patients with severe liver inflammation; histological analysis of pre-treatment liver biopsies may help to identify patients most likely to benefit from the antiviral regimen.

Consistency and applicability of return to function guidelines in tactical-athletes with exertional heat illness. A systematic review.

OBJECTIVE: To assess the consistency of return to sport and occupation recommendations following EHI provided in published clinical practice guidelines, consensus statements, position statements, and practice alerts. The agreement between medical policies governing the return to duty following EHI between the branches of the United States Armed Forces and published recommendations was assessed. METHODS: Ovid MEDLINE, Web of Science, and CINAHL databases were searched for clinical practice guidelines and position statements published at any time that guided return to activity in individuals with EHI. Methodological quality was assessed, and the specific recommendations for clinical management were extracted. Consistency of recommendations was evaluated. Agreement between published guidelines and the policies governing return to activity in military tactical athletes with heat injury were also evaluated. RESULTS: Guidelines developed by two civilian sports medicine societies in the United States detailing recommendations for return to function following EHI were identified. There was consistency between guidelines regarding recommendations that addressed abstinence from activity; medical follow-up; graded resumption of activity; and return to function. Pertaining military policy, contemporary regulations published in recent years reflected the recommendations provided in the professional guidelines. The greatest incongruence was noted in older military policies. CONCLUSIONS: This systematic review highlights the need for consistent recommendations across all branches of the military and medical specialties pertaining to returning servicemembers to duty after EHI .

Clinicopathologic features and molecular analysis of enterovirus 71 infection: report of an autopsy case from the epidemic of hand, foot and mouth disease in China.

A 15-month boy with fatal hand, foot, and mouth disease (HFMD) exhibited atypical symptoms and progressed rapidly to death. An autopsy was performed the next day and tissue sections were stained for histopathological examination. His intestinal samples were tested for enterovirus 71 (EV71), and the whole-genome sequence of EV71 was analyzed. An autopsy revealed that the central nervous system, lungs, and gut displayed severe meningitis and brainstem encephalitis, remarkable pulmonary congestion, edema, moderate inflammatory infiltration, and hemorrhage as well as intestinal mucosal congestion, epithelial necrosis, thinning intestinal wall, and submucosal lymphoid follicular hyperplasia. The heart showed myocardial interstitial congestion, myocardial edema, and some inflammatory infiltrates. There were no significant alterations in the architecture of other organs. EV71 antigen and apoptotic cells were detected in brain, lung and intestine by immunohistochemical staining and TUNEL (TdT-mediated dUTP nick-end labeling) respectively. Intestinal contents and intestinal autopsy samples of this case were positive for EV71, and the EV71 strain was classified as subgenogroup C4. In China, the severe forms of HFMD were mostly caused by EV71 subgenogroup C4 infection. Severe intestinal damages may relate to EV71 subgenogroup C4 infection. Thus, children with severe EV71 HFMD may have serious pathological changes in their central nervous system, lungs, and gut. Physicians should pay special attention to infants with atypical symptoms, particularly in EV71 epidemic areas for early diagnosis and treatment.

Two-staged time-dependent materials for the prevention of implant-related infections.

Infection is a main cause of implant failure. Early implant-related infections often occur in the first 4 weeks post-operation. Inhibiting bacterial adhesion and biofilm formation at the early stage and promoting subsequent implant osseointegration are important for implant success. Our previous studies demonstrated that dimethylaminododecyl methacrylate (DMADDM) provided dental materials with antibacterial effects. In the present study, DMADDM and hydroxyapatite (HA) are loaded on to the titanium (Ti) surface via poly dopamine (PDA) self-polymerization. This local DMADDM-delivery Ti is referred as Ti-PHD. Here we report the two-staged capability of Ti-PHD: (1) in the first stage, releasing DMADDM during the high-infection-risk initial period post-implantation for 4 weeks; (2) then in the second stage, enhancing osteogenesis and promoting osseointegration. Ti-PHD has a porous surface with higher average roughness and greater hydrophilicity than pure Ti. Its biocompatibility is verified in vitro and in vivo. During the first 4 weeks of release, both DMADDM remaining on Ti surface and DMADDM released into the soaking medium greatly reduced the adherence and growth of pathogens. This is further confirmed by the prevention of bone destruction in a rat osteomyelitis model. After releasing DMADDM for 4 weeks, Ti-PHD promotes osteogenic differentiation of human bone marrow mesenchymal stem cells (hBMSCs) and new bone formation around the implants in vivo. This article represents the first report on the two-staged, time-dependent antibacterial and osteogenesis effects of Ti-PHD, demonstrating its potential for clinical applications to inhibit implant-associated infections. STATEMENT OF SIGNIFICANCE: The present study develops a two-staged time-dependent system for local dimethylaminododecyl methacrylate (DMADDM) delivery via Ti implant (referred to as Ti-PHD). DMADDM and hydroxyapatite (HA) are loaded on to the Ti surface with poly dopamine (PDA). Ti-PHD can release DMADDM during the high-risk period of infection in the first stage, and then promote osseointegration and new bone formation in the second stage. This bioactive and therapeutic Ti is promising to inhibit infections and enhance implant success.

Efficacy and safety of interferon alpha-2b versus pegylated interferon alpha-2a monotherapy in children with chronic hepatitis B: a real-life cohort study from Shanghai, China.

BACKGROUND: Interferon alpha (IFN-α) is a preferred therapy for antiviral treatment of children with chronic hepatitis B (CHB) aged > 1 year currently. Peginterferon alpha-2a (Peg-IFN α-2a) is a recommended international guideline for treatment of CHB children, which is limited to children aged > 3 years. But the exact efficacy and safety of IFN-α and Peg-IFN α-2a for treating CHB are not sufficient. METHODS: Clinical manifestations, baseline characteristics, related laboratory tests and adverse events were retrospectively analyzed in children with CHB, who visited Children's Hospital of Fudan University and were treated with IFN α-2b or Peg-IFN α-2a monotherapy and followed up from January 2003 to October 2018. RESULTS: A total of 36 immune-active patients without advanced fibrosis were enrolled to be treated with IFN α-2b (group A, n = 18) or Peg-IFN α-2a (group B, n = 18). IFN α-2b or Peg-IFN α-2a was administered for a median of 48 weeks subcutaneously by body surface area (BSA) category at a dose of 3 MU/m2 or 104 µg/m2, respectively. HBV e antigen (HBeAg) seroconversion rates at 48 weeks post-treatment were higher in group A than group B (92.9% vs. 87.5%), so as the rates of HBsAg clearance (22.2% vs. 11.1%), and hepatitis B virus (HBV)-DNA < 1000 IU/mL (88.9% vs. 83.3%). Only mild flu-like symptoms and transient neutropenia appeared in some children at the early stage of treatment. No severe abnormal results was observed in other laboratory assessments. CONCLUSION: The antiviral monotherapy of 48-week IFN α-2b or Peg-IFN α-2a in children with CHB is well tolerated and effective, which is associated with higher rates of HBeAg seroconversion and HBsAg clearance than in adults and previously pediatric patients.

Effects of water and microbial-based aging on the performance of three dental restorative materials.

The objective of this study was to evaluate the performance changes of three restorative materials before and after three different aging treatments: storage in distilled water, Streptococcus mutans (S. mutans) and oral salivary microbes suspensions for one month. Resin composite (RC), giomer and glass ionomer cement (GIC) were chosen for aging procedures. Surface morphology, roughness average (Ra), color changes and mechanical properties were all determined before and after aging respectively. Biomass and metabolism difference of early attached biofilm on the material surface were tested through 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and lactic acid measurement. The results showed that after S. mutans or salivary microbes aging treatments, GIC group displayed significant morphology changes, with Ra value significantly higher than that before aging (p < .001). Color changes of giomer and GIC group after S. mutans aging were not clinically acceptable. All materials after two microbial-based aging treatments had higher flexural strength than that before aging (p < .05). Giomer after salivary microbes aging had higher elastic modulus than the initial values (p < .05). Additionally, early attached biofilm biomass and lactic acid production in GIC group after S. mutans or salivary microbes aging were higher than that before aging (p < .05). While one-month water aging showed less influences on material performance to some extent. In conclusion, to better simulate the harsh oral environment, in vitro microbial-based aging models showed more advantages in evaluating dental restorative materials' degradation over time.

[Line scanning analysis of white porcelain from Gong Kiln in early Tang dynasty by energy disperse X-ray fluorescence].

Gong kiln, for its long porcelain-firing history, was one of three representative white porcelain kilns in northern China. In order to improve the quality and whiteness of white porcelain, a decorating layer or cosmetic earth was laid on the body surface in Gong kiln during early Tang dynasty, which was able to blot out rough surface and weaken the influence of fuscous body upon surface color. In this paper the main chemical composition of the white porcelain's profile was analyzed by using energy disperse X-Ray fluorescence. The result showed that different materials were used as cosmetic earth during early Tang dynasty, in accordance with the phenomenon under optical microscope. In addition, the glaze belongs to calcium glaze in which plant ash was added.

[HBV genotype and liver histology effect of peginterferon alpha treatment of HBeAg-position chronic hepatitis B].

OBJECTIVE: To investigate the efficacy of PEG-interferon alpha (PEG-IFN alpha) treatment of HBeAg-positive chronic hepatitis B and HBV genotypes and liver tissues effect of HBeAg seroconversion. METHODS: 54 cases confirmed by liver biopsy, genotype clear HBeAg positive chronic hepatitis B (CHB) patients according to body weight, respectively, subcutaneous injection of PEG-IFN-alpha2a 135 microg or 180 microg, or PEG-IFN-alpha2b 50 microg, 80 microg or 100 microg once weekly treatment for 48 weeks and followed for 24 weeks after discontinuation. Statistics of HBeAg seroconvertion, HBV genoty pes and liver histology e antigen seroconversion after the end of treatment. RESULTS: 54 patients were followed up at the end of HBeAg seroconversion rate was 29.63% (16/54). Genotype B patients with HBeAg seroconversion rate was 35.29%, 27.03% higher than the C-type patients, but the difference was not statistically significant (chi2 = 0.382, P = 0.537). Inflammation of the liver activity highter ( > G2) , the degree of fibrosis heavier ( > S1) HBeAg seroconversion rate (50.00% vs. 25.00%, 40.90% vs. 21.88%), but were not statistically significant (chi2 = 1.391, 1.444, P = 0.238, 0.229). Activity of HBV genotype, liver inflammation, liver fibrosis and other factors by multivariate Logistic regression analysis, only liver inflammation activity of the important factors of HBeAg seroconversion. CONCLUSION: Important factors, liver inflammation activity of PEG-interferon alpha treatment of HBeAg-position chronic hepatitis B patients and HBV genotypes and liver fibrosis may be of little significance.